He said the bus was escorted by police to the terminal, where passengers are now collecting their luggage and waiting to be driven to Luton.

A spokesman for the National Air Traffic Services (NATS) earlier said airspace over the capital had not closed: “There was some disruption this morning but airspace is absolutely not closed at the moment.”

Speaking after the incident, Stansted Airport confirmed: “A Ryanair aircraft diverted into London Stansted at approximately 8.55am this morning.

Armed police met the flight (Image: @zulu_wooloo)

“The aircraft which was flying from Kaunas to Luton, landed safely with Essex Police in attendance.

“Flight operations were briefly held while the aircraft landed and taxied to its parking stand.

“The airport is open and flights are arriving and departing as normal.”